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Overview

A bunion forms when the bursa (a sac of fluid at friction points between the tendons and bone in some areas and between bone and the skin in others) becomes inflamed along the edge of the joint at the base of the big toe. There are two types of bunions. The acute bunion causes the sharper pain. It develops from a bursitis, a sudden outcropping of a fluid-filled sac. An acute bunion can progress into the second type of bunion, the hallux valgus, a chronic but often painless deformity involving permanent rigidity of the bones. Bunions can form in any part of the foot but occur most often at the big toe joint, where the first metatarsal bone abuts the proximal phalanx of the big toe. Women are more likely than men to get bunions because of the misshapen footwear and elevated heels they wear.

Causes
Essentially, bunions are caused by a disruption of the normal interworking of the bones, muscles, ligaments and tendons that comprise your feet, often from wearing shoes that squeeze the toes or place too much weight-bearing stress on them. However, it should be pointed out that other causes or factors in the development of bunions can include flat feet or low arches in the feet, some forms of arthritis, problems with foot mechanics, foot injuries and neuromuscular disorders such as cerebral palsy. Arthritis in the MTP joint, for example, can degrade the cartilage that protects it, and other problems may cause ligaments to become loose. Pronation, walking in a way that your foot rolls inwards, increases your risk for developing bunions.
SymptomsMost patients complain of pain directly on the bunion area, within the big toe joint, and/or on the bottom of the foot. The bunion may become irritated, red, warm, swollen and/or callused. The pain may be dull and mild or severe and sharp. The size of the bunion doesn?t necessarily result in more pain. Pain is often made worse by shoes, especially shoes that crowd the toes. While some bunions may result in significant pain, other bunions may not be painful at all.

Diagnosis
Bunions are readily apparent - the prominence is visible at the base of the big toe or side of the foot. However, to fully evaluate the condition, the foot and ankle surgeon may take x-rays to determine the degree of the deformity and assess the changes that have occurred. Because bunions are progressive, they don?t go away, and will usually get worse over time. But not all cases are alike - some bunions progress more rapidly than others. Once your surgeon has evaluated your bunion, a treatment plan can be developed that is suited to your needs.

Non Surgical Treatment
Bunion pain can be successfully managed in the vast majority of cases by switching to shoes that fit properly and don't compress the toes. Your orthopaedic surgeon can give you more information about proper shoe fit and the types of shoes that would be best for you. Follow these general points of shoe fit. Do not select shoes by the size marked inside the shoe. Sizes vary among shoe brands and styles. Judge the shoe by how it fits on your foot. Select a shoe that conforms as nearly as possible to the shape of your foot. Have your feet measured regularly. The size of your feet change as you grow older. Have both feet measured. Most people have one foot larger than the other. Fit to the largest foot. Fit at the end of the day when your feet are the largest. Stand during the fitting process and check that there is adequate space (3/8" to 1/2") for your longest toe at the end of each shoe. Make sure the ball of your foot fits well into the widest part (ball pocket) of the shoe. Do not purchase shoes that feel too tight, expecting them to "stretch" to fit. Your heel should fit comfortably in the shoe with a minimum amount of slippage. Walk in the shoe to make sure it fits and feels right. (Fashionable shoes can be comfortable.) Some shoes can be modified by stretching the areas that put pressure on your toes. Splints to reposition the big toe and orthotics (special shoe inserts shaped to your feet) also may relieve pain. For bunions caused by arthritis, medications can be prescribed to reduce pain and swelling.


Surgical Treatment
There are many different procedures described to correct bunions. You should be aware that usually just shaving the bunion off, although it is attractive and minimally invasive, is usually not enough. Initially the foot will look much better but with time the bunion will recur. Arthrodesis refers to surgery performed on the great toe joint where the joint is fused. This is usually reserved for people with very severe deformities when other surgical options are impossible. Bunionectomy refers to the simple removal of the bunion itself. This is seldom used because it doesn?t correct the underlying bone problems. Osteomety is the commonest surgical procedure. The bone is cut and the bones realigned and pinned in place until they heal so that the underlying bone deformity is corrected and the bunion will not recur. The resection arstplasty refers to the removal of the toe joint and this creates a flexible scar that functions as the joint instead. In the past there has been some interest in implanting artificial joints but this has fallen out of favor due to the fact that they usually do not hold up with the normal every day stress that people put their feet through.